[S390] System call cleanup.

Remove system call glue for sys_clone, sys_fork, sys_vfork, sys_execve,
sys_sigreturn, sys_rt_sigreturn and sys_sigaltstack. Call do_execve from
kernel_execve directly, move pt_regs to the right place and branch to
sysc_return to start the user space program. This removes the last
in-kernel system call.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
index 887a9881d0d0..80a54a0149ab 100644
--- a/arch/s390/kernel/compat_signal.c
+++ b/arch/s390/kernel/compat_signal.c
@@ -255,9 +255,9 @@ sys32_rt_sigaction(int sig, const struct sigaction32 __user *act,
 }
 
 asmlinkage long
-sys32_sigaltstack(const stack_t32 __user *uss, stack_t32 __user *uoss,
-                                                        struct pt_regs *regs)
+sys32_sigaltstack(const stack_t32 __user *uss, stack_t32 __user *uoss)
 {
+        struct pt_regs *regs = task_pt_regs(current);
         stack_t kss, koss;
         unsigned long ss_sp;
         int ret, err = 0;
@@ -344,8 +344,9 @@ static int restore_sigregs32(struct pt_regs *regs,_sigregs32 __user *sregs)
         return 0;
 }
 
-asmlinkage long sys32_sigreturn(struct pt_regs *regs)
+asmlinkage long sys32_sigreturn(void)
 {
+        struct pt_regs *regs = task_pt_regs(current);
         sigframe32 __user *frame = (sigframe32 __user *)regs->gprs[15];
         sigset_t set;
 
@@ -370,8 +371,9 @@ badframe:
         return 0;
 }
 
-asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs)
+asmlinkage long sys32_rt_sigreturn(void)
 {
+        struct pt_regs *regs = task_pt_regs(current);
         rt_sigframe32 __user *frame = (rt_sigframe32 __user *)regs->gprs[15];
         sigset_t set;
         stack_t st;
@@ -407,8 +409,8 @@ asmlinkage long sys32_rt_sigreturn(struct pt_regs *regs)
         return regs->gprs[2];
 
 badframe:
-        force_sig(SIGSEGV, current);
-        return 0;
+        force_sig(SIGSEGV, current);
+        return 0;
 }       
 
 /*